When Seth MacFarlane decided it was time to temporarily kill off "Family Guy's" dog, Brian, he was trying to teach a lesson.

"It reminded people this is still a show where anything that can happen despite the fact it’s been on for awhile," MacFarlane explained to TV critics at the Television Critics Association's winter press tour.

With that being the goal, MacFarlane considers the stunt a mission accomplished. But what he didn't expect is for the viewers to teach him a lesson, too.

After announcing its new fall season, and teasing the new seasons of hits like "Glee," Fox had one more surprise up its sleeve at Monday's upfront presentation for advertisers.

Seth MacFarlane, creator of Fox animated series "Family Guy," "American Dad" and "The Cleveland Show," told attendees that he was working on another show for 2013: a re-imagining of the first-ever primetime animated sitcom, "The Flintstones."